Device for retouching profiled pulleys



June 5, 1956 1. PIRKNER 2,748,642

DEVICE FOR RETOUCHING PROFILED PULLEYS Filed Jan. 4, 1951 2 Sheets-Sheet 1 Fig. 3

INVENTOR I. Fibrin/e1 BY v ,4 v ZTTORNEYS June 5, 1956 1. PIRKNER DEVICE FOR RETOUCHING PROFILED PULLEYS 2 Sheets-Sheet 2 Filed Jan. 4, 1951 United States Patent 2,748,642 DEVICE FOR RETOUCHING PROFILED PULLEYS Ignaz Pirlmer, Graz-Andritz, Austria, assignor to Maschinenfabrik Andritz Actieugesellschaft, Graz-Andritz, Austria Application January 4, 1951, Serial No. 204,305

Claims priority, application Austria January 7, 1950 7 Claims. (Cl. 82-7) The invention relates to a device for retouching profiled pulleys, and in particular worn-out rope sheaves.

The duration of service of hauling and hoisting ropes and cables is greatly influenced by the profile or section of the sheave. During each rope (or cable) period the rope wearingly grinds oit the bottom of the profile of the sheave and burrows into same even often to the extent of a few millimeters. Considering the elongation which the ropes undergo during use, the diameter of the rope is correspondingly reduced, and so is the diameter of the worn-out profile of the rope sheave, so that said profile tallies with the reduced diameter of the rope. A hauling or hoisting rope, newly put into commission, will therefore, unless the sheave is altered, be laterally clamped and thus be exposed to a higher wear and tear from the very beginning. In case of older sheaves, already heavily worn, this may even cause serious damages to the rope. In hauling and hoisting ropes, and in particular in such as are used for the transport of human beings, the number of the outwards visible rope strands, which are found damaged on a certain distance, are considered as the determining factor deciding whether the rope should continue in use 01' not, so that by such damages the duration of life of valuable ropes is greatly reduced as they must be prematurely removed. However, retouching worn-out rope sheaves is, with the means hitherto known, only possible in case of sheaves correctly centred and running perfectly true. Such sheaves are already now retouched at the place of operation using special driving devices and ordinary carriages or slides. As a rule, however, such retouching work is only possible in sizeable shops or factories so that in case of emergency either spare sheaves have to be kept in stock, or a relatively long shut-down has to be put up with. Experience teaches that sheaves are very often distorted and/or non-circular so that, if at all, they can only be retouched a limited number of times, whilst with larger-size sheaves no repair by way of retouching has been possible. These large-size sheaves are relatively expensive, so that in many cases a heavier wear and tear of the rope is put up with in order to avoid the necessity of renewing the sheaves.

The invention has for its object to eliminate these drawbacks, the process for retouching such sheaves substantially consisting in that a tracer, controlled by the profile or section to be retouched, is used for maintaining unaltered the relative position of the carrier of the retouching tool in respect to the profile portion of the rotating sheave which at the same moment is within the range of said tool, whilst the feed motion of the retouching tool goes on in harmony with the profile shape desired i, e. independently of the control motion of the tool carrier. According to the invention the tracer, controlling the tool carrier, acts in the neighbourhood of the working tool on two points of the profile to be retouched, located symmetrically as far as this is possible.

It is also convenient to proceed in such a manner that with a tool preferably operating at two points Within 2,748,642 Patented June 5, 1956 the profile, at the same time, first the running area for the tracer is retouched which afterwards will serve as a guide for working the remaining parts of the profile.

In this manner it is possible to return or regrind also heavily distorted sheaves without having to remove more material than required for correcting the profile. A retouching operation of this kind does not perceptibly reduce the dimensions of the sheave, so that this operation can be repeated several times e. g. with each change of rope. Hence, it is possible to retouch not only centrically rotating, but also radially or laterally worn and/ or distorted rope sheaves in their operating positions, whereby the driving force may not only be derived from the devices already known, but also from means operatively available e. g. by the rope running over the sheave to which then a somewhat reduced speed may be imparted for this purpose. This does away with the necessity of dismounting the rope sheave, or the like, to be retouched and renders it possible to carry out the work without having to interrupt operations.

The appliance provided by the invention for retouching such profiled discs (sheaves) is substantially characterized by the carriage of the retouching tool being supported e. g. on a cross-slide so as to be movable in all directions in a plane located transversely to the faces to be retouched, and being connected to a tracer guided on the profile to be worked in the neighbourhood of the retouching area, said tracer determining the relative position of the carriage in respect to the profile to be acted upon, whereas the retouching tool itself isindependently of the control motion of the carriagemovably and rockably or turnahly supported by same. Consequently, the tool itself can be controlled by hand in the manner used on ordinary lathes, Whilst the carriage is guided in conformity with the profile to he retouched.

Preferably, the retouching installation is portable and is so designed as to be attachable to any fixture. Hence, it may e. g. be fixed to the derrick itself so that the sheaves can be retouched in their operating positions. But just as well the device can be employed in workshops, when the sheave can be fixed to the face plate of a lathe or a vertical turning machine or mill.

It follows from the above that invention renders it possible to retouch distorted and non-circular rope sheaves, which hitherto used to defy repair, besides presenting also sub antial advantages in case of not-distorted sheaves and profiled discs of other kind.

The drawing diagrammatic represents a device of this type with reference to an embodiment given by way of example.

Fig. l is a front elevation of the device according to the invention during the retouching of a rope sheave.

Fig. 2 is a side elevation.

Fig. 3 is a detail.

Figure 4 illustrates a device according to Figures 1 and 2 in operating position retouching a rope sheave on a hoisting tower, and

Figure 5 is a fragmentary transverse View partly in cross-section through the arrangement of Figure 4.

By means of an intermediate setting-up plate It the device is fixed to any kind of base which in this particular case is constituted by two angle irons 2. On the plate the carriage, holding the retouching tool 3, is supported by means of the cross-slides 4 and 5 in such a manner as to be movable in all directions of one plane. In the manner generally employed in lathes the carriage is fitted with cross-slides 6 and 7 so that the retouching tool, e. g. the cutter 3, can be displaced by hand according to the rope sheave profile desired. A further possibility of motion consists in the guide 8 of the slide 7 being so attached to the slide 5 as to be rotatory about the axis of the screw 9 which signifies that the tool 3 can always be set to the correct cutting position.

The slide 5 which rockably or turnably supports the carriage consisting of the parts 6, 7, 8 is provided with a roller 10 running in the rope sheave profile 11, to be retouched, and thus controlling the slide 5 together with the carriage supported by same according to said profile that the carriage follows the distortions and the eccentricities of the sheave 11.

A weight-loaded cable 13 running over the roller 12 urges the slide 4 on to the profile 11 to be retouched. Two further cables 15, passing over rollers 14, exercise a pull on the slide 5, whereby, according to the cutting pressure of the tool 3, one of them is loaded with a weight for balancing the cutting pressure, in particular whenever the cutter 3 acts on the flanks of the profile 11. Thus the weight-loaded cables 13 and/or 15 will hold the roller 10 in continuous contact with the profile to be retouched. The pressure of the roller 10, together with the slide 5 and the entire carriage, in at least two directions against the profile to be retouched may also be brought about in another way, e. g. by spring loading, by hydraulic or pneumatic pressing-on devices, and the like. The turning tool 3 may also be replaced by a grinding wheel. When using the device according to the invention in a workshop the mounting or settingup plate 1 may without difficulty be formed into a standard.

Considering the unequal wear, which yields an irregular and undefined profile, the invention provides for the use of a tracer wheel 10 doubly contacting the rope sheave profile according to the embodiment shown in Fig. 3 the spreading angle of which, as referring to the rounding of the profile, will advantageously vary between 60 and 120. This prevents a distortion of the controlmotion by the profile bottom which, as a rule, is worn out irregularly. In combination with said tracer wheel retouching is preferably begun with a tool having two cutting faces symmetrical to the axes by means of which simultaneously the two contacting faces for the tracer can be worked. In order to protect the tracer wheel against chips falling down, said chips are blown off by means of a jet of compressed air, or the wheel is screened e. g. by a metal sheet.

Figure 4 illustrates the mechanism disclosed in Figure 2 in operating position and retouching a rope sheave or pulley on the hoisting tower of a mine shaft. The rope sheave consists, and as shown in Figure 5, of a hub 16 from which extend riveted arms 18 connected to and supporting the rim of peripheral portion 17, the profile of which is to be retouched. This rope sheave has, for example, a diameter of six or more millimeters. The rim part 17 in most cases is only approximately 1 in. thick. With sheaves of this character the peripheral rim 17 is frequently deformed laterally or radially by as much as 1 in. or more so that reworking or overhauling the sheave on a lathe is no longer possible. The retouching or reprofiling of the sheave can be carried out only if, in the manner according to this invention, allowance is made for such deformations and only the profile form 11 is corrected. In Figure 4 the hub 16 is mounted on an axle 19 in a journal 20 which is fastened to a supporting frame 21 on the hoisting tower, not illustrated. Over the rope sheave runs hoisting rope 22. A hoisting cage, not shown, is fastened to the rope portion 22 and the rope portion 22 passes to the hoist, not shown.

The drawing illustrates an arrangement which renders it possible to reprofile or rework the sheave while it is in its operating position on the hoisting tower. The device, constituting an improvement in accordance with this invention, and denoted by the arrow A, is fastened to the support frame 21 by securing the angle irons 2 thereto. The rope sheave is turned slowly by the rope in the direction of the arrow B and the speed of turning is in accordance with the admissible cutting speed. It has been demonstrated that in this manner within eight hours a rope sheave may be overhauled by two men Without removing the rope and without an interruption of operation taking place. If, however, the sheave must be removed for the purpose of overhauling, it requires a larger number of men to reprofile the same and a considerable interruption of operation of the mine shaft.

The weight 23 acting on slide 4, which carries slide 5, presses slide 4 toward the rope sheave. The weight 24 maintains slide 5 in position against the cutting pressure of tool 3. In this manner the feeler or tracing roller 10 is continuously held in contact with the profile 11, Figure 5, and slide 5 is so controlled that it follows all motions of profile 11 which result from a radial or lateral deformation and this slide is always held in unchanged posi tion relative to the respective profile section that is adjacent the operating tool 3. On the support constituted by slides 5 and 4, the tool 3 can be manually controlled according to the desired form of profile 11.

This device renders it possible to retouch at any time worn-out, heavily distorted or non'circular sheaves for ropes, and the like, either in a workshop or on the spot, and in particular directly on the derrick and even with the rope remaining on the sheave, whereby it is advisable to make use of the lowest rope speed. Of course, the sheave to be retouched may also be operated by a driving pulley fixed to the shaft or to the sheave itself.

What I claim is:

1. Means for re-machining the rope groove of profiled pulleys comprising a base disposable adjacent a rotatable pulley the rope groove of which is to be remachined, crossed slides supported on said base, a tracer means carried by one of the slides and including angularly related contact surfaces contactable with the pulley groove at symmetrically related regions on opposite sides of the apex of the groove, means for moving the slides toward and maintaining the tracer means in contact with the pulley groove including separate means applying force to the tracer means in at least two directions so that the tracer means follows the contour of the pulley groove regardless of radial or lateral deformations, a tool means, tool carrying saddle means mounted on said crossed slides for any movement in a plane parallel to the plane of movement of the tracer means, said tool means being directed toward the periphery of the pulley and separate means for moving the tool respectively toward and transversely of the rope groove, independent of the movement of said crossed slides.

2. Means for re-machining the rope groove of profiled pulleys as defined in and by claim 1 in which the slides comprise upper and lower slides, said tracer means being carried by the upper slide, the separate means applying force to the tracer means including a first means connected to the lower slide for applying force to move both said slides and thus said tracer means toward and into contact with said pulley groove and at least one other means connected to the upper slide for moving the same transversely of the groove and including means exerting a force at least sufficient to equalize the machining pressure of the tool.

3. Means for refinishing the rope groove of sheaves, particularly sheaves that are deformed laterally and radially comprising a base adapted to be disposed adjacent the profiled periphery of a sheave to be refinished, crossed slides mounted on the base, and including upper and lower slides with relation to a sheave rotatable about a horizontal axis, both slides being simultaneously movable toward the sheave profile and the upper slide being movable transversely thereof, a tool carrying saddle supported by the slides and in turn including upper and lower crossed slides and a base, means rockably mounting the second mentioned base on said first mentioned upper slide, means for feeding one of the slides of said second mentioned upper and lower slides toward the periphery of the sheave, independent means for feeding the other of said slides transversely of the sheave, a tool carried by said last mentioned upper slide, and directed toward the periphery of the sheave, a tracer means connected to the first mentioned upper slide and extending toward the sheave, means for simultaneously moving said first mentioned group of slides toward the sheave periphery to place and maintain said tracer means in con tact therewith when the sheave is rotated toward and successively past said tool and tracer means, and means applying lateral force to the upper slide of said first mentioned group of slides and therefore to said saddle and tool sufiicient to equalize the cutting pressure of said tool to move the same transversely of the sheave periphery, so that the last two mentioned means maintain said tracer means in contact with the groove regardless of lateral or radial deformations thereof.

4. Means for refinishing the rope groove of sheaves as defined in and by claim 3 in which the means for simultaneously moving the first mentioned group of slides toward the sheave periphery and the means for applying lateral force to the upper slide of said group comprise weight loaded cables.

5. Means for refinishing the rope groove of sheaves as defined in and by claim 3 in which the tracer means comprises a roller having angularly diverging sheave contacting surfaces so as to contact and follow the contour of the groove of the sheave at symmetrically related regions on opposite sides of the apex of the said sheave groove.

6. Means for refinishing the rope groove of sheaves defined in and by claim 5 in which the tool is profiled and contacts the sheave periphery between the regions contacted by the contacting surfaces of the roller.

7. Means for refinishing the rope groove of sheaves as defined in and by claim 6 in which the angle of divergence of the sheave contacting surfaces of the roller is such that the regions contacted thereby are from to apart.

References Cited in the file of this patent UNITED STATES PATENTS 734,639 Wallenstein July 28, 1903 998,656 Tattershall July 25, 1911 1,239,486 Highams Sept. 11, 1917 1,644,006 Beck Oct. 4, 1927 1,668,512 Miller May 1, 1928 2,000,129 Dunnam May 7, 1935 2,000,300 Scruby May 7, 1935 2,039,719 Kline et a1. May 5, 1936 2,213,002 Hall Aug. 27, 1940 

